[decomp] Use new squeeze.dims overload in decompositions (#91602)
This removes the now-redundant `_squeeze_multiple` helpers and instead decomposes into a single call to `aten::squeeze.dims` which also has the effect of reducing the lowered graph size in inductor.
Pull Request resolved: https://github.com/pytorch/pytorch/pull/91602
Approved by: https://github.com/ngimel